Reorganize usings and apply minor formatting changes

Reorganized `using` directives in `InvoiceDescriptor20Reader.cs`:
- Moved `using System.IO;` up
- Removed `using System.Text;`, `using System.Xml;`, and `using System.Xml.XPath;`

Applied minor formatting changes:
- Added space after `foreach` keyword
- Added space after `if` keyword
- Added space after `FromString` method call in `AdditionalReferencedDocument` method

Author: amroel

ZUGFeRD/InvoiceDescriptor20Reader.cs

@@ -18,11 +18,9 @@
  */
 using System;
 using System.Collections.Generic;
+using System.IO;
 using System.Linq;
-using System.Text;
 using System.Xml;
-using System.Xml.XPath;
-using System.IO;
 
 
 namespace s2industries.ZUGFeRD
@@ -158,7 +156,7 @@ public override InvoiceDescriptor Load(Stream stream)
             };
             var financialCardId = XmlUtils.NodeAsString(doc.DocumentElement, "//ram:ApplicableHeaderTradeSettlement/ram:SpecifiedTradeSettlementPaymentMeans/ram:ApplicableTradeSettlementFinancialCard/ram:ID", nsmgr);
             var financialCardCardholderName = XmlUtils.NodeAsString(doc.DocumentElement, "//ram:ApplicableHeaderTradeSettlement/ram:SpecifiedTradeSettlementPaymentMeans/ram:ApplicableTradeSettlementFinancialCard/ram:CardholderName", nsmgr);
-            
+
             if (!string.IsNullOrWhiteSpace(financialCardId) || !string.IsNullOrWhiteSpace(financialCardCardholderName))
             {
                 _tempPaymentMeans.FinancialCard = new FinancialCard()
@@ -169,7 +167,7 @@ public override InvoiceDescriptor Load(Stream stream)
             }
 
             retval.PaymentMeans = _tempPaymentMeans;
-            
+
             retval.BillingPeriodStart = XmlUtils.NodeAsDateTime(doc.DocumentElement, "//ram:ApplicableHeaderTradeSettlement/ram:BillingSpecifiedPeriod/ram:StartDateTime", nsmgr);
             retval.BillingPeriodEnd = XmlUtils.NodeAsDateTime(doc.DocumentElement, "//ram:ApplicableHeaderTradeSettlement/ram:BillingSpecifiedPeriod/ram:EndDateTime", nsmgr);
 
@@ -193,18 +191,18 @@ public override InvoiceDescriptor Load(Stream stream)
                     retval.CreditorBankAccounts.Add(_account);
                 } // !for(i)
             }
-            
+
             var specifiedTradeSettlementPaymentMeansNodes = doc.SelectNodes("//ram:ApplicableHeaderTradeSettlement/ram:SpecifiedTradeSettlementPaymentMeans", nsmgr);
 
             foreach (var specifiedTradeSettlementPaymentMeansNode in specifiedTradeSettlementPaymentMeansNodes.OfType<XmlNode>())
             {
                 var payerPartyDebtorFinancialAccountNode = specifiedTradeSettlementPaymentMeansNode.SelectSingleNode("ram:PayerPartyDebtorFinancialAccount", nsmgr);
-                
+
                 if (payerPartyDebtorFinancialAccountNode == null)
                 {
                     continue;
                 }
-                
+
                 var _account = new BankAccount()
                 {
                     ID = XmlUtils.NodeAsString(payerPartyDebtorFinancialAccountNode, ".//ram:ProprietaryID", nsmgr),
@@ -304,7 +302,7 @@ public override InvoiceDescriptor Load(Stream stream)
             retval.DuePayableAmount = XmlUtils.NodeAsDecimal(doc.DocumentElement, "//ram:SpecifiedTradeSettlementHeaderMonetarySummation/ram:DuePayableAmount", nsmgr, 0).Value;
 
             // in this version we should only have on invoice referenced document but nevertheless...
-            foreach(XmlNode invoiceReferencedDocumentNodes in doc.DocumentElement.SelectNodes("//ram:ApplicableHeaderTradeSettlement/ram:InvoiceReferencedDocument", nsmgr))
+            foreach (XmlNode invoiceReferencedDocumentNodes in doc.DocumentElement.SelectNodes("//ram:ApplicableHeaderTradeSettlement/ram:InvoiceReferencedDocument", nsmgr))
             {
                 retval.AddInvoiceReferencedDocument(
                     XmlUtils.NodeAsString(invoiceReferencedDocumentNodes, "./ram:IssuerAssignedID", nsmgr),
@@ -357,7 +355,7 @@ public override bool IsReadableByThisReaderVersion(Stream stream)
 
             return _IsReadableByThisReaderVersion(stream, validURIs);
         } // !IsReadableByThisReaderVersion()
-        
+
 
         private static TradeLineItem _parseTradeLineItem(XmlNode tradeLineItem, XmlNamespaceManager nsmgr = null)
         {
@@ -367,12 +365,12 @@ private static TradeLineItem _parseTradeLineItem(XmlNode tradeLineItem, XmlNames
             }
 
             string _lineId = XmlUtils.NodeAsString(tradeLineItem, ".//ram:AssociatedDocumentLineDocument/ram:LineID", nsmgr, String.Empty);
-            
+
             LineStatusCodes? _lineStatusCode = default(LineStatusCodes).FromString(XmlUtils.NodeAsString(tradeLineItem, ".//ram:AssociatedDocumentLineDocument/ram:LineStatusCode", nsmgr, null));
             LineStatusReasonCodes? _lineStatusReasonCode = default(LineStatusReasonCodes).FromString(XmlUtils.NodeAsString(tradeLineItem, ".//ram:AssociatedDocumentLineDocument/ram:LineStatusReasonCode", nsmgr, null));
 
             TradeLineItem item = new TradeLineItem(_lineId)
-            {                
+            {
                 GlobalID = new GlobalID(default(GlobalIDSchemeIdentifiers).FromString(XmlUtils.NodeAsString(tradeLineItem, ".//ram:SpecifiedTradeProduct/ram:GlobalID/@schemeID", nsmgr)),
                                         XmlUtils.NodeAsString(tradeLineItem, ".//ram:SpecifiedTradeProduct/ram:GlobalID", nsmgr)),
                 SellerAssignedID = XmlUtils.NodeAsString(tradeLineItem, ".//ram:SpecifiedTradeProduct/ram:SellerAssignedID", nsmgr),
@@ -392,7 +390,7 @@ private static TradeLineItem _parseTradeLineItem(XmlNode tradeLineItem, XmlNames
                 BillingPeriodEnd = XmlUtils.NodeAsDateTime(tradeLineItem, ".//ram:BillingSpecifiedPeriod/ram:EndDateTime/udt:DateTimeString", nsmgr),
             };
 
-            if(_lineStatusCode.HasValue && _lineStatusReasonCode.HasValue)
+            if (_lineStatusCode.HasValue && _lineStatusReasonCode.HasValue)
             {
                 item.SetLineStatus(_lineStatusCode.Value, _lineStatusReasonCode.Value);
             }
@@ -422,7 +420,7 @@ private static TradeLineItem _parseTradeLineItem(XmlNode tradeLineItem, XmlNames
             }
 
             if (tradeLineItem.SelectSingleNode(".//ram:AssociatedDocumentLineDocument", nsmgr) != null)
-            {                
+            {
                 XmlNodeList noteNodes = tradeLineItem.SelectNodes(".//ram:AssociatedDocumentLineDocument/ram:IncludedNote", nsmgr);
                 foreach (XmlNode noteNode in noteNodes)
                 {
@@ -557,7 +555,7 @@ private static AdditionalReferencedDocument _getAdditionalReferencedDocument(Xml
             return new AdditionalReferencedDocument
             {
                 ID = XmlUtils.NodeAsString(node, "ram:IssuerAssignedID", nsmgr),
-                TypeCode = default(AdditionalReferencedDocumentTypeCode).FromString(XmlUtils.NodeAsString(node,"ram:TypeCode", nsmgr)),
+                TypeCode = default(AdditionalReferencedDocumentTypeCode).FromString(XmlUtils.NodeAsString(node, "ram:TypeCode", nsmgr)),
                 Name = XmlUtils.NodeAsString(node, "ram:Name", nsmgr),
                 IssueDateTime = DataTypeReader.ReadFormattedIssueDateTime(node, "ram:FormattedIssueDateTime", nsmgr),
                 AttachmentBinaryObject = !string.IsNullOrWhiteSpace(strBase64BinaryData) ? Convert.FromBase64String(strBase64BinaryData) : null,